<!DOCTYPE html>
<html lang="en" xmlns:sec="http://www.w3.org/1999/xhtml">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
欢迎<span sec:authentication="principal.username"> ------</span><a href="/logout">退出登录</a>
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</body>
</html>